Skip Navigation Bar
 

National Information Center on Health Services Research and Health Care Technology (NICHSR)

History of Health Services Research Project

\ Interview Index

HISTORICAL INSIGHTS INTO THE DEVELOPMENT OF HEALTH SERVICES RESEARCH: A NARRATIVE BASED ON A COLLECTION OF ORAL INTERVIEWS

By Edward Berkowitz, Ph.D.

"I was really from the beginning, interested in services, access to care, improving the quality of services, how to make hospitals better institutions."1 Although trained as a nurse,therefore,Linda Aiken, who became a distinguished health services researcher, chose not to become involved in the provision of clinical care. Instead, she wanted to know how the hospital worked and to put that knowledge to use in improving the hospital. This desire to see the system whole, rather than to interact with individual patients, appears to be one of the field's distinguishing features. The series of interviews conducted with important figures in health care services research helps explain the motivation and intellectual outlook of individual practitioners; it also provides an inexact, but nonetheless suggestive, outline of the field's development.

The Influence ofKerr White

Kerr White's ideas and style of leadership helped to establish the field. At base his contributions stemmed from a fundamental sense of dissatisfaction both with the clinical conduct of medicine, as practiced and taught at leading medical centers, and with the intellectual content of more socially and publically oriented fields, such as public health and hospital administration. Receiving his medical training in Canada, White described hearing lectures on "how to dig a pit privy and how to can tomatoes so that you wouldn't get botulism and other dreary subjects." He pledged that "he wouldn't have much to do with public health as practiced by these kinds of guys." As his career advanced, he came to believe that "the general discourse and level of intellectual activity is considerably lower in schools of public health than medical schools." As for hospital administrators, they appeared to be concerned with cutting "down the noise from the garbage cans" and other "nuts and bolts stuff" that White tended to dismiss. At the same time, White found much to criticize about the conduct of medicine. He worried that some medical interventions did more harm than good. In a study conducted while White was at the University of North Carolina, he found that many things went wrong in patient referrals from general practitioners to specialists in university medical centers. "We found massive misconduct among the referring physician, the patient, the medical student at our Clinic, the attending physician and sometimes other participants in the referral process," he noted. In a study of outpatient medical care at the UNC hospital's outpatient clinic, White discovered "laboratory results that wereoverlooked, errors that were made, things that weren't done...."

Where others might have been content simply to catalogue these shortcomings, White managed to fashion a coherent intellectual critique of the medical system. In the course of thinking about what he called the "ecology" of medical care in 1961, White grew interested in the importance of what he labelled as "primary care" in the health care system. Perhaps his chief insight was that for every 1,000 adults only one ended up in a university medical center, yet the medical schools trained physicians to treat that one person and thus neglected the other 999. Expanding on this finding, a large study sponsored by the World Health Organization and involving researchers in twelve countries yielded the general result that "where there was adequate primary care, that is there are readily available general physicians, hospital utilization was much less than when the converse was true, no matter what the country."

Barbara Starfield, a Johns Hopkins pediatrician trained in both medicine and public health, participated in the international utilization study, which was conducted while White was at Johns Hopkins. Starfield's work on the study began a process that led to her realization that people misunderstood the flaws of America's health care system. As she put it in her interview for this project, "I resonated so much with what White wrote about, in terms of my own experience, my own work in communities of children -- that was the first time I'd encountered anybody who brought a scholarly view to a field that was at that time considered an unscientific field." Starfield joined White's department at Hopkins and came to believe that, "We can improve the health of socially deprived population groups if we focus our attention on the kind of health services that they especially need, and that's primary care services, not speciality care -- ongoing care with physicians who appreciate and recognize their problems."

The connection between White and Starfield illustrated that White was an important mentor for others in health services research field. AfterCharles Flagle, among others, suggested that White be brought to Hopkins, White, who arrived in 1964, became the founding chairman of the Department of Health Care Organization. He soon metJack Wennberg, who later emerged as an important figure in the field of healthcare epidemiology. White advised Wennberg to look at hospital discharge dates from the state of Vermont (White had previously worked at theUniversity of Vermont). Accepting that advice, Wennberg mined the data for variations in the rate of using various medical procedures across hospitals and geographical regions. That led to his work in evaluating the efficacy of clinical services. AsPaul Cleary described Wennberg's work, he examined treatments "about which there is a lot of variability and about which there is either controversy or ambiguity about the best way to do things," such as the prostatectomy. In this way, Wennberg tried to explain variations in outcome in order to improve the quality of care. In the areas of utilization and quality, therefore, White exerted influence both through his own work and through that of his students.

Avedis Donabedian and the Qualitv of Care

Quality of care became an important concern of the health care research field.Avedis Donabedian did perhaps the most important work in this area. Barbara Starfield, among others, indicated her intellectual debt to Donabedian. Like White, who was born in Canada and went to medical school at McGill, Donabedian approached the American medical care system as something of an outsider. Born and trained as a physician in the middle east, Donabedian came to the Harvard School of Public Health and received an MPH degree in 1955. Although he had practiced medicine in Jerusalem, he never did clinical work in the United States. Instead, he used his position at theUniversity of Michigan's School of Public Health to observe, as he put it, "how these 'natives' think... What are the given values that seem to run this system. Why is it the way it is." These observations led him to formulate a general model of quality assurance that contained components related to structure, process, and outcome and, according to the Institute of Medicine, "guided two decades of research and program development."2

Toward the National Center for Health Services Research and Development

Donabedian did his work largely in isolation. White, by way of contrast, worked hard to create a network of people and institutions in order to give the field of health services research a professional identity. While still at the University of North Carolina, White saw a notice in the Journal of the American Medical Association for grants in the field of "hospital and medical facilities." These grants were funded through the Hill-Burton hospital construction program, created in 1946 to increase the supply of hospital beds in rural areas and expanded in 1954 to include grants to the states to construct rehabilitation facilities and other institutions concerned with chronic disease. He applied for a grant and received "a fair package of money" to study physician referrals. White believed that the research grants from the Hill-Burton program constituted the first formal federal support of health services research. Eventually, White became involved in the study section that awarded the grants. In 1959 he helped to change its name from the Hospital and Medical Facilities Study Section to the Health Services Research Study Section.Charles Flagle andCecil Sheps, connected with Johns Hopkins and the University of North Carolina respectively, were also prominent study section members.

When White became chair of the study section in 1963 (he says 1962 -- an example of the imprecision in oral interviews), he decided "we should try to put our new field on the academic map."3 He thought in terms of the ways that the National Science Foundation and the National Institutes of Health had established other fields. Hence, he worked to create research awards for young investigators, as a means of luring them into the field, and to fund university-based Health Services Research Centers, as a means of establishing the presence of health service researchers in and around medical schools. A chief virtue of the work to be done at these centers was to be interdisciplinary collaboration. "Economics, sociology, epidemiology, and management theory" all were to be involved in the new endeavor.

"What we need now that we've created these things going on, is to create a National Center for Health Services Research," White told a group of interested people assembled in the Palmer House hotel. He proceeded to draw a plan for such a center on a napkin. Although the Association of American Medical Colleges, a group representing the interests of American medical schools, failed to support the idea with enthusiasm, White and others proceeded to lobby officials of the Department of Health, Education and Welfare. Phil Lee, long identified with the social aspects of the provision of medical care and at the time (1966? 1967? -- again it is hard to tell from the oral interview) the Assistant Secretary for Health at HEW, became a supporter. The National Center for Health Services Research and Development came into existence on May 2,1968.4 Health services research had acquired what amounted to its own National Institute of Health. As White put it, "we thought there should be a visible and substantial entity charged with examining as many aspects as it could of the health services enterprise." Among the concerns of the new Center were to be "quality, access, costs, efficacy, and efficiency."

The National Center in Operation

The members of White's department proved to be important beneficiaries of grants distributed by the National Center.Barbara Starfield, for example, received a career development award in the late 1960s that enabled her to expand her thinking on the subject of quality assurance.Charles Flagle, a Hopkins engineer and an expert on operations research, received money from the Center. At the same time the Center attracted a great deal of criticism.Edward Hinman, a Public Health Service official who ran a PHS hospital in Baltimore, complained that the Center funded too little research of practical value to him. He describedGerald Rosenthal, a Harvard economist brought in to run the Center, as "way out of touch with the delivery of care." "Was your job to fund the economists and the psychologists and the industrial engineers or was your job to try to get things down to a practical level?" Hinman wondered.

Although White had no qualms about the academic nature of the Center's work, he too grew critical of it. In the 1970s the Center took on too many conceptual problems and, as Whiteput it, "indulged in scatteration." Soon, too, the Center found itself in a debilitating competition for tinds with other government organizations engaged in health services research, such as the National Center for Health Statistics and the Health Care Financing Administration. By the time this last agency was created in 1977, the Center, according to White, had fallen "on hard times."

The Health Care Financing Administration, the subject of another oral history project, ran the Medicare and Medicaid programs, a fact that underscored an important feature in the historical development of federally funded health services research.5 The campaign to create a National Center for Health Services Research and Development coincided almost exactly with the effort to pass and implement Medicare. Although Medicare and Medicaid represented the federal government's most important health care commitments and were the primary reasons that the federal government became the country's single largest health insurer, their design and administration owed little or nothing to the field of health services research. In part, this situation reflected the relative isolation of the Public Health Service and the field of public health more generally from questions related to health care financing. As a consequence the passage of Medicare in 1965 had little effect on the Public Health Service.6 In part, too, this situation stemmed from the intensely political atmosphere in which Medicare was passed. The founders of Medicare did not want to challenge the conduct of medical care so much as they wanted to assure access to that care on the part of the elderly. They accepted the structure of health care -- the very thing that White and his colleagues sought to challenge -- and proposed only to alter some of its financing arrangements. What mattered was political bargaining in order to pass the legislation. Hence, very little of what might be described as health services research went into the design of Medicare. AsWilbur Cohen, an HEW official who was perhaps the central Kennedy and Johnson administration figure in the fight for Medicare, noted, "There was only a limited amount of experience with large-scale, nationwide, health reimbursement programs. There was a good deal of rhetoric and little empirical information. There was an extensive outpouring of ideology and a limited amount of research."7 As the need for that research grew, it led to research conducted first by the Social Security Administration and, after 1977, by the Health Care Financing Administration. The Center for Health Services Research and Development tended to be shut out of the action.

In the Medicare program, as in American health care more generally, the concerns of policymakers soon shifted from access to cost. Indeed, when the National Center for Health Care Research and Development was under consideration in the Senate, the Committee on Labor and Public Welfare cited "continued increases in the price of medical care" as a rationale for the Center's existence.8 In time, then, the field of health services research turned its attention to the technical issues and quality concerns related to cost containment. An important point in this process was the RAND health insurance experiment.

RAND and the Health Insurance Experiment

Located in the Los Angeles area, the RAND corporation became a center of health services expertise that rivaled White's Johns Hopkins department in terms of importance and influence. It would, however, be misleading to imply a rivalry between RAND and academic institutions such as Hopkins, since people educated by White at Hopkins, such as Robert Brook, played key roles in the health insurance experiment. The impetus for the experiment came not so much from clinicians such as Brook, concerned about health outcomes, as from economists, who focused their attention on the relationship between the cost of medical care and its consumption. RAND had developed an institutional expertise in the application of quantitative methods to the conduct of defense policy. In 1967, a year of implementation for many Great Society social programs, the organization decided it wanted to become involved in domestic policy and in the particular areas of education and health. It invited Gerald Rosenthal, the same Harvard professor who would later head the National Center for Health Services Research and Development, to spend the summer of 1967 at RAND. Rosenthal refused but suggested thatJoseph Newhouse, one of his promising graduate students, take his place. Newhouse's summer experience led him eventually to become a full-time RAND employee. At this time, around 1968, Newhouse considered himself to be an applied micro-economist, not someone with a primary orientation toward health services research but rather someone with the methodological expertise to work on a wide range of social problems. "I never expected to get into health care as deeply as I ended up doing," he said.

The health insurance experiment became Newhouse's primary activity at RAND. It originated in a grant funded by the National Center for Health Services Research and Development to study "the question of whether and how utilization responded to insurance." An economist at the Office of Economic Opportunity (OEO), an important center for applied social research in the federal government that had already started a major social experiment to test the effects of a negative income tax (guaranteed annual income) on work and social behavior, grew interested in Newhouse's work and "suggested to me that I might want to think about the desirability and feasibility of an experiment." According to Newhouse, "the hope was that a controlled experiment in the social sciences could do what the controlled trial had done in medicine." The experiment, launched by OEO and after the demise of that agency taken over by the Department of Health Education and Welfare, involved offering different types of health insurance plans to people in five sites across the country and observing the differences in the utilization of care and health outcomes. By the time the study ended in 1982, Newhouse and his associates had acquired a plethora of data.

The results of the health insurance experiment were important in themselves and as an impetus for further work in the field. The data confirmed the expectations of economic theory that as the rate of cost sharing for health care rose, the consumption of health care fell. By the time these results became public, the Reagan administration had dashed the commonly held assumption that the United States would create some form of national health insurance. To the extent that the experiment was intended to anticipate the creation of national health insurance, therefore, it failed in its purpose. Nonetheless, the data proved useful to employers and other private sector health care financers. Newhouse attributed at least part of the big increase in initial cost sharing that occurred in the 1980s to the experiment. More than paving the way for managed care, which became a distinguishing feature of both public and private health care in the 1980s and 199Os, the experiment also supplied the impetus for research that helped to fine tune that care and to protect its recipients from adverse health outcomes. AsKathleen Lohr, one of the many health services researchers attracted to RAND by the health insurance experiments, noted, cost-sharing in and of itself was a "blunt instrument for trying to reduce the use of ineffective and unnecessary services." In other words, it tended to reduce services in an indiscriminate fashion -- the good along with the bad. Furthermore, the experiment showed that cost-sharing had adverse effects on the health of vulnerable groups, such as low-income children, "just a catastrophic drop in the use of services, clearly services that were needed as well as services that weren't that you didn't see so much for kids with a higher income." Such findings put a premium on relating the effects of different health care arrangements, such as health maintenance organizations, to health outcomes and spawned the next generation of health services research in the managed care era.

Measuring Health Outcomes

The people from RAND played important roles in this next generation of research. John Ware, an expert in psychometrics, received a grant from the National Center for Health Services in the summer of 1972 to study what he described as "health perceptions and patient perception." Only a graduate student at the time, Ware attended a conference to present his work and met someone from RAND. As a result, he received an invitation to consult with the team working on the measurement of health outcomes in the health insurance experiment. That led to permanent employment at RAND and an opportunity to develop forms that allowed people to assess their health status. Work on the health insurance experiment enabled Ware to participate in the Medical Outcome Study, which was originally conceived of as a manpower study -- should family practitioners or cardiologists treat heart disease -- but evolved into a study of health outcomes indifferent settings -- do chronically ill people have equally good outcomes if there are treated in a prepaid, as opposed to fee-for-service plan. Started at the University of Chicago under the direction of Alvin Tarloff, the project ultimately received a home at RAND, and Ware became the lead investigator. "We basically were using the brain trust at RAND to design the study and to plan and do the data collection," Ware said. His leadership role on the Medical Outcome Study underscored the validity ofKathleen Lohr's observation that "the common era of measuring health status and qualify of life in effect can be traced to the Health Insurance Experiment and the set of people who developed the original questionnaires for measuring health status" includingRobert Brook and John Ware.9

If Ware led the Medical Outcome Study, Brook played an instrumental role in the Health Services and Utilization Study. The advent of managed care made it imperative to find a means of determining the appropriate use of particular procedures. Brook and Mark Chassin developed a set of indications for the appropriate use of particular procedures, such as endoscopy. When they tested these guidelines against experience in the Medicare program, they discovered, as Joseph Newhouse explained, that "there were . . . fairly high absolute percentages of inappropriate use of these procedures and, surprisingly, that the rate of percentage of inappropriate did not vary by the overall rate." In other words, places where a procedure such as endoscopy was done frequently did not have a higher rate of inappropriate use of the procedure than did places that did endoscopies less frequently. Something more complicated was at work.

The Robert Wood Johnson Foundation

The Medical Outcome Study received funding from the Robert Wood Johnson Foundation among other sources. During the 198Os, at a time when federal funding for health services had become moribund, this Foundation, the largest private philanthropy devoted to health, helped fill some of the gaps. Along with RAND and Johns Hopkins and the other major academic centers, RWJ, as it became known to health services research practitioners, developed into an important center of expertise that had the added virtue of being able to advance the research agenda by funding specific projects. Here again the Hopkins connection proved important.Robert Blendon, another ofKerr White's students, worked withDavid Rogers, a former Hopkins medical school Dean, to staff the Foundation and to outline its program. Blendon served as a mentor and collaborator toLinda Aiken, aUniversity of Wisconsin post doctoral fellow in medical sociology whom he recruited to the Foundation. When she arrived in 1974 to the recently started Foundation, Aiken found her work exciting because "we all thought our work was paving the way for National Health Insurance." In time the Foundation developed a basic approach which Aiken described as taking an idea "that had been tested some place" and trying "it out in a more diverse set of circumstances." As an evaluator of such projects, Aiken had the job of showing that the idea would work " if it was mainstreamed" and made part of the health care financing system, either through Medicare and Medicaid or through private insurance.

As it became clear that Medicare would pay for less and less and that national health insurance would not become a reality, the Foundation's role became to preserve the field of health services research at a time of federal austerity. As Aiken noted, "there were still a lot of reformers left in the federal government but without any portfolio, and they wanted to test somebody's ideas." In effect, the Foundation, which enjoyed close links to government reformers and academic researchers, enabled those tests to be carried out. In time both Aiken and Blendon gained enough stature in the research community to be able to move from the Foundation to theUniversity of Pennsylvania and Harvard respectively. Coming to the University of Pennsylvania in1987, Aiken started the Center for Health Services and Policy Research.

An Association for the Profession

In thinking about her professional identity, Linda Aiken described the Association for Health Services Research as "my real peer group." The formation of this Association in 1981reflected both the shock of recognition among researchers in geographically dispersed settings that they would benefit from a common forum and the fear that federal support for health services would erode in the Reagan era. A journal already existed, in part because of a federal grant to the American Hospital Association that Kerr White facilitated. Although the Association wanted to call the journal "hospital research," White insisted on it being called "something like health services research." The problem of a common professional identity for a widely disparate field remained. Kathleen Lohr related her experiences during the seventies of going to the large American Public Health Association Meetings and attending the Medical Care Section. In time, a Committee on Health Services Research held discussions before the APHA meeting started because "the Health Care Section didn't quite get it with respect to what health services research was." Ultimately, the leaders of the field decided there was a need for a separate association. JohnWare remembered sitting in Robert Brook's living room "when everyone was in the room talking about creating an association that would be a professional group and maybe a lobbying organization."

Whether or not the Association played a role, the federal government decided to reinvigorate its program of research support for health services with the creation in December, 1989 of the Agency for Health Care Policy and Research. As with the earlier Center, the Agency's creation did not solve the problem of funding which, almost by definition, was permanent. Part of the problem was that health services researchers were often messengers who brought bad news: they could not always tell government sponsors or clinical practitioners things that they wanted to hear. As a field, health services research always ran the risk of offending its patrons, asKerr White discovered during his tenure at Johns Hopkins (he left in 1977 after a stay of some thirteen years). Nonetheless, such endeavors as clinical outcomes research held the promise of providing useful information about, as Linda Aiken put it, "the cost-quality trade-offs in care, what really makes a difference and what doesn't." In a pragmatic sense, it enabled the field to receive money from the NIH, with its orientation toward research on specific diseases and its steady and comparatively large funding base.

Concluding Remarks

A small group of interviews yields only impressionistic evidence that cannot substitute for exhaustive research in secondary and other primary sources. At the same time, the emphasis that the interviews put on personal recollection makes them a distinctive way to get at the motivations behind policy actions and to discover the networks of people who worked on a common methodological problem or who sought to advance a political goal. This process yields data, not available elsewhere, that illuminates the historical development of a field.

In this essay I have emphasized the role of Kerr White as a linchpin in the creation of modem health services research. His work at North Carolina, Johns Hopkins and elsewhere brought him into contact not only with the leaders of his generation, such as Cecil Sheps, but, in his role as teacher, with the leaders of the next generations as well. In this manner, White's influence spread beyond Johns Hopkins to include researchers at the other major centers of activity, such as RAND and the Robert Wood Johnson Foundation. It helped too that White self-consciously sought to advance the identity of the field, as his efforts to create the National Center for Health Services Research and Development demonstrated.

Interviews introduce the problem of self-selection to historical narrative. By focusing on White, one risks the possibility of overstating his influence. If for example, the interviews had centered on Cecil Sheps and his colleagues, a different picture might have emerged. At the very least, however, these interviews provide an overview of the changing preoccupations of the field -- from access to cost to the trade off between cost and quality, for example -- and give a sense of its development over time.

--------------------------------------------------------------------------------

Notes

1. All quotations are from the interviews I conducted for the National Library of Medicine unless otherwise noted.

2. Institute of Medicine, Medicare: A Stratergy for Qualitv Assurance Volume 1, Kathleen N. Lohr editor, (Washington: National Academy Press, 1990), p. 53.

3. For background on this matter and for the 1963 date, see E. Evelyn Flook and Paul J.Sanazaro, "Health Services Research: Origins and Milestones," in Flook and Sanazaro eds., Health Services Research and R & D in Perspective (Ann Arbor: Health Administration Press,1973), pp. 77-78.

4. See Paul J. Sanazzaro, "Federal Health Services R & D Under the Auspices of the National Center for Health Services Research and Development," in Flook and Sanazaro eds., Health Services Research and R & D in Perspective, p. 152.

5. These interviews are available on the world wide web at the Social Security Administration's history website or at the library of the Health Care Financing Administration. For more on the creation of HCFA see Joseph Califano, Governing America: An Insider's Report from the White House and the Cabinet (New York: Simon and Schuster, 1981).

6. A fact noted by historian John Parascandola on pages 491-492 of his entry on the Public Health Service that appeared in George Thomas Kurian ed., A Historical Guide to the U.S. Government (New York: Oxford University Press, 1998).

7. Wilbur Cohen, "Reflections on the enactment of Medicare and Medicaid," Health Care Financing Review, 1983 Annual Supplement, p. 3.

8. Sanazarro, "Federal Health Services R & D Under the Auspices of the National Center for Health Services Research and Development," p. 151.

9. Interestingly, Lohr's husband had given Ware his original grant at the Center for Health Services Research and Development, which is the sort of personal coincidence that oral interviews can reveal.


INDEX


Agency for Health Care Policy and Research 9
Aiken, Linda 1 8 9
American Hospital Association 8
American Public Health Association 8
Association of American Medical Colleges 3
Baltimore 4
Blendon, Robert 7 8
Brook, Robert 5 7 8
Canada 1 2
Center for Health Services and Policy Research 8
Chassin, Mark 7
Chicago, University of 7
Cleary, Paul 2
Cohen, Wilbur 5 10
Department of Health, Education and Welfare 4
Donabedian, Avedis 2 3
Ecology of Medical Care 1
Efficacy 2 4
Epidemiology 2 3
Flagle, Charles 2 3 4
Great Society 5
Harvard University 3 4 5 8
School of Public Health 3
Health Administrators 1
Health Care Financing 5 8
Health Care Financing Administration 4 5 10
Health Economists 4 5 6
Health Insurance Experiment 5 7
Health Services Research 2 3 4 5 6 7 8 9
Hill-Burton Act 3
Hinman, Edward 4
Jerusalem 3
Johns Hopkins University 2 3 4 5 7 8 9
Department of Health Care Organization 2
Johnson, Lyndon B. 5
Journal of the American Medical Association 3
Kennedy, John F. 5
Lee, Dr. Philip Randolph 4
Lohr, Kathleen 6 7 8 10
Los Angeles 5
McGill University 2
Medicaid 4 8 10
Medical Care Administration 1 4
Medical Outcome Study 7
Medicare 4 5 7 8 10
Michigan, University of 3
National Center for Health Services 3 4 5 6 7 10
National Center for Health Services Research and Development 3 4 5 6 9 10
National Center for Health Statistics 4
National Health Insurance 8
National Institutes of Health 3
National Science Foundation 3
Newhouse, Joseph 5 6 7
North Carolina, University of Chapel Hill 1 3 9
Office of Economic Opportunity 6
Pennsylvania, University of 8
Public Health Service 4 5 10
Quality of Care 1 2 3 4 5 9
Questionnaires 7
RAND 5 6 7 9
Reagan, Ronald 6 8
Robert Wood Johnson Foundation 7 9
Rogers, David 8
Rosenthal, Gerald 4 5
Sheps, Cecil 3 9
Social Security Administration 5 10
Starfield, Barbara 2 4
Tarloff, Alvin 7
U.S. Congress Senate 5
U.S. Department of Health, Education and Welfare 4 5 6
University-based Health Services Research Centers 3
Vermont 2
Vermont, University of 2
Ware, John 7 10
Wennberg, Jack 2
White, Kerr 1 2 3 4 5 8 9 10
Wisconsin, University of 8
World Health Organization 2

Return to Top